Level 3
The total weight of 5 cartons and 7 crates of apples is 130 kg. Each crate of apples weighs thrice as heavy as a carton of apples. How much does each carton of apples weigh?
Level 3
At the bus interchange, some passengers boarded the bus. At the first stop, 17 passengers alighted and 3 passengers boarded the bus. At the second stop, only 24 passengers boarded the bus. When the bus left the second stop, there were 54 passengers on the bus. How many passengers boarded the bus at the interchange?